UV-pretreatment- and near-infrared rapid thermal annealing-enhanced dehydrogenation for a-Si:H thin films at 400 °C

• An enhanced dehydrogenation process for flexible substrates as well as glass substrates is proposed..
• UV pretreatment and NIR-RTA are used..
• Temperature of the LTPS process for a-Si:H thin films could be reduced by 40 °C..
• Dehydrogenation time of the LTPS process could be reduced by 20 min..

A new dehydrogenation processing method was developed for the low-temperature polysilicon process. This method can reduce both the process temperature and time through the combination of an ultraviolet pretreatment (UVP) process with near-infrared rapid thermal annealing (NIR-RTA). NIR-RTA using tungsten-halogen lamps was observed to reduce the dehydrogenation time by approximately two thirds and the temperature by approximately 20 °C compared to conventional furnace processing. The UVP process was able to lower the dehydrogenation temperature by a further 20 °C. Thus, the new dehydrogenation process, consisting of UVP followed by NIR-RTA, could achieve a hydrogen concentration of 1.97 at.% in 20 min at 360 °C.